Limitations and future work

This work implements high-throughput computing to systematically investigate the torsional properties of three types of chiral nanofibres and their bundles’ structure with various enantiomer configurations. There are several limitations of this research, and many aspects of the high-throughput process need to be improved.

x The accuracy of the empirical force field for describing the nanomaterials directly determines whether the results obtained are reliable or not. Currently, the AIREBO potential used in the simulation can only provide qualitative quantities of most carbon nanothreads. Thus, for high-throughput modelling, accurate potentials for all the nanocarbon materials need to be developed.

x The materials studied are free structures, while in the real world, defect-free nanofibres can hardly be obtained. Therefore, investigating the effects of the existence of the defects will provide great references for their applications.

x This research only investigates the torsional properties of three nanofibres.

There is still a large state space for the properties of the nanofibres with various configurations not yet explored. Thus, a high-throughput framework needs to be developed to conduct the simulations and process the data.

x As the state space of the properties is extremely large, it is infeasible to conduct simulations for all the models. To find the best way of designing the materials to meet certain requirements, active learning methods need to be developed to guide high-throughput computing to reach the targets with minimum effort.

x To verify the findings of the simulations, experimental works should be conducted in future. The feedback information will help to improve the accuracy of the intelligent learning methods.

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Appendices

Appendix A: The enumeration program.

Figure A-1: Python code for bundle structure enumeration

Appendix B: The bond breaking detection program.

Figure A-2: LAMMPS code for bond breaking detection

Appendix C: Gravimetric densities and twist strain rate of nanofibre bundles.

Figure A-3: Gravimetric energy density densities and twist strain rate of PT bundles

Figure A-4: Gravimetric energy densities and twist strain rate of stiff-chiral-3 NTH bundles

Figure A-5: Gravimetric Energy densities and twist strain rate of (8, 3) CNT bundles